Quality Fish Meal Research Articles

A novel “on-off-on” electrochemiluminescence aptasensor based on resonance energy transfer as signal amplification strategy for ultrasensitive detection of sulfadiazine in different samples

The misuse of antibiotics may contaminate the environment and cause harm to human health. Therefore, rapid and accurate detection of antibiotics is essential. In this study, a novel electrochemiluminescence resonance energy transfer (ECL-RET) pair was designed using a new ECL emitter (CPM, Ce-TBAPy) as the donor and Co-MOF@AuPt as the acceptor. Moreover, a highly sensitive and specific “on-off-on” ECL aptasensor was constructed for detecting sulfadiazine (SDZ). The aptasensor exhibited a broad linear range (from 10.0 fg mL−1 to 100 ng mL−1) for the SDZ concentration, with limit of detection and limit of quantification values of 1.14 fg mL−1and 3.75 fg mL−1, respectively. The aptasensor achieved good results in spiking experiments with milk and egg samples, and successfully quantified SDZ in fish meal quality control sample. The prepared aptasensor presents great potential for food and environmental safety by detecting antibiotics.

The Influence of Acid and Cooking Methods on The Quality of Fish Meal Processed from by-products of Catfish Fillet Processing

Catfish fillet processing produces a by-product dominated by heads (25- 28%) and bones (11-13%). This study aims to process fish meal from by- products of catfish using different treatments, namely soaking in a 4% formic acid solution (F) and a 4% hydrochloric acid solution (H), as well as cooking techniques involving boiling (R) and steaming (K). Observations were made on the yield, pH, proximate analysis, calcium content, NPN (non-protein nitrogen), TBA (thiobarbituric acid), microbiological tests, sensory evaluation, and amino acid profiles. The research showed that soaking in acid caused a decrease in pH, protein content, and TBA and increased the fat content of the resulting fish meal. The optimal treatment for the highest quality fish meal is steaming without acid treatment. In this treatment, the protein content meet the requirements of the SNI 01.2725.01.2013 as grade 3 fish meal, with a yield of 22.83%, a pH of 6.86, a moisture content of 6.2 ± 0.3%, an ash content of 27.33 ± 0.7%, and a protein content of 45.5 ± 1.3%. Analysis of the amino acid profile of fish meal from that treatment showed a better amino acid composition compared to commercial fish meal. The fish meal contained essential amino acids in sufficient quantities, with higher levels compared to the amino acid standards set by FAO/WHO 2013 for human nutritional needs, and met the requirements as a nutritional ingredient for fish and livestock feed.

Effectiveness of the Organic Acid-Based Antimicrobial Agent to Prevent Bacterial Contamination in Fish Meal.

Animal feed production is an important step of the food animal production chain in a farm-to-table model. The contamination of raw ingredients with foodborne pathogens in feed production remains as an important safety issue where pathogens may spread into food animals to cause illnesses in humans when affected food animals are consumed. In the present study, we aimed to examine the quality and microbial contamination of fish meal and to investigate the effectiveness of the organic acid-based antimicrobial agent SALTEC 514TM against Salmonella to prevent bacterial contamination in fish meal. Fish meal samples (n = 4) collected from feed mills at different locations were analyzed for protein and total volatile basic nitrogen (TVBN) content to assess their nutritional value and freshness, and its microbiological quality. The protein and TVBN content ranged from 53.2 ± 3.1 to 67.5 ± 2.3 g/100 g and 73.8 ± 4.5 to 100.4 ± 11.2 mg/100 g meal, respectively. Total plate count of the fish meal samples ranged from 2.0 ± 0.3 to 4.5 ± 0.5 log units, whereas suspected foodborne bacteria, Escherichia coli and Salmonella, were not detected in all samples. Fish meal samples were artificially contaminated (day 0) and re-challenged (day 30 and 90) with Salmonella Enteritidis (3 log CFU/g) to test for the effectiveness of SALTEC 514TM, an organic acid-based antimicrobial formulation, in preventing Salmonella contamination and recontamination during storage. SALTEC 514TM, when applied at three different doses, was found to reduce the number of Salmonella in monitored samples after one day of storage. A low dose of 0.5 kg/ton SALTEC 514TM prevented Salmonella recontamination from occurring in fish meal samples stored for 37 days. In medium (1.0 kg/ton) and high doses (3.0 kg/ton), applications of SALTEC 514TM prevented the Salmonella recontamination for a maximum storage duration of 97 days. The application of SALTEC 514TM in fish meal and/or other feed ingredients may prove to be a safe alternative to reduce the microbial load, especially of foodborne-related microorganisms, to contribute to feed and food safety.

Kualitas Tepung Ikan di Pesisir Pantai Kabupaten Merauke Sebagai Bahan Pakan

Catch fish that are not used as food can be processed into fish flour. The purpose of this study was to analyze fish meal from several types of fish found on the coast of Merauke RegencyThis test is carried out to see the physical and chemical quality.. From the research results of this study obtained the physical quality of fish meal can be which is categorized, both in mixing feed food and storage namely: the average density of 0.58 gr / cm3, surface area 53.88 cm2, pH 6.25, threshold power 1.15 m / sec and stack angle 27.260C, average ash content of 6.31%, protein 65.46%, fat 5.46%, crude fiber 0 and water content an average of 6.32%, These results indicate the quality of fish meal is included in standard I based on the quality of SNI 2013 as feed material. Eight (8) types of fish meal that have low economic value and potential to be developed as feed ingredients include Kaca fish (Kurtus gulliveri, Pasir fish (Platycephalus endrachtensis), Bete-Bete fish (Rhinoprenes pentanemus), Duri Herkules fish (Arius sp), and Duri putih fish (Arius leptaspis).

Near Infrared feature waveband selection for fishmeal quality assessment by frequency adaptive binary differential evolution

Fishmeal is a high-energy feed. Fishmeal quality has an important influence on animal growth. The detection of ash content is essential for evaluating fishmeal quality. Near infrared (NIR) spectroscopy is a rapid detection technique that can be used to determine the ash content in fishmeal. The wavelength related to the target component must be selected in NIR quantitative analysis considering that the NIR spectrum has a strong correlation. In this paper, the adaptive binary differential evolution (ABDE) algorithm was proposed for feature selection. The algorithm was an improvement of the mutation operator of binary differential evolution (BDE) and improved binary differential evolution (IBDE) algorithms. The performance of the BDE, IBDE, and ABDE algorithms was compared in secondary wavelength selection on 11 combined intervals selected by the move window partial least squares (MWPLS) algorithm. The performance of the model established by the ABDE algorithm in feature selection was superior to that constructed by the BDE and IBDE algorithms. Frequency ABDE (FABDE) was designed by introducing frequency into the ABDE algorithm to minimize the influence of random factors. The root mean square error (RMSET) and the correlation coefficient (RT) of the FABDE model for the test set were 1.160 ​% and 0.941, respectively. By comparison, the RMSET and the RT of the ABDE model were 1.212 ​% and 0.935, respectively. The results of model prediction indicated that the FABDE algorithm proposed herein can be feasibly used to improve the model effects for the rapid NIR analysis of ash content in fishmeal.

Effect of Freshness on Fish Meal Quality; Anchovy Meal

Balık unu av sezonunda fazla avlanan veya ekonomik değeri olmayan balıklar ile balık artıklarından üretilmektedir. Karadeniz’den 2007-2008 balıkçılık av sezonunda avlanan hamsi balıklarından (Engraulis engrasicholus, L) üretilen balık unu araştırılmıştır. Sinop ilinde farklı üretim teknikleri uygulayan 3 balık unu fabrikasında (A, B ve C fabrikaları) 8 saat arayla hammaddeden numuneler alındı. TVB- N ve TBA analizleri yapılarak ve T1, T2, T3 ve T4 tazelik grubu oluşturuldu. A, B ve C fabrikalarından T1, T2, T3 ve T4 tazelik gruplarında meydana gelen kalite değişimlerini belirlemek amacıyla ham protein, ham yağ, ham kül, nem, aminoasit, yağ asit kompozisyonu ve renk değişimleri incelendi. Elde edilen istatistiki değerlendirmeler neticesinde tazelik gruplarında hammadde bayatladıkça balık ununda ham protein, esansiyel aminoasit, esansiyel olmayan aminoasit, doymuş yağ asitleri, çoklu doymamış yağ asitleri, EPA, DHA, omega3, omega6 ile omega3/omega6 oranının azaldığı belirlenmiştir. Balık ununda ham yağ ve nem oranının hammadde bayatladıkça arttığı tespit edilmiştir. Görülen farkların istatistiki olarak önemli olduğu sonucuna ulaşılmıştır (p

Використання беззубки звичайної (Anodonta cygnea (Linne, 1758)) як добавки до рибного корму на прикладi африканського сома (Clarias gariepinus (Burchell, 1822))

Purpose. Uzbekistan aquaculture has a huge deficit of balanced feed. In a case of feed production from local ingredients, the problem is the lack of stable source of animal protein. The purpose of this experiment was to find out how swan mussel Anodonta used as a feed additive for African catfish will affect fish growth. Methodology. Minced Anodonta was prepared as follow: mussels were collected from the bottom of ponds after fish harvesting; the collected mussels were kept in the separate aquarium; every day several mussels were taken out, their shells were opened and muscle parts were separated the (mostly mussel leg); then the separated muscle were kept for disinfection in KMnO4 solution of low concentration during 20 min and then crushed to a minced state. Feed was given to African catfish according to a special scheme at the rate of 7% of the fish weight. The control group did not receive the minced mussels and fish were fed with carp feeds.The mixed feed in the experimental group #1 consisted of 50% carp feed and 50% minced mussel. In the experimental group #2, African catfish were fed with minced mussels only. Findings. The experiment showed the clear advantage of feed containing 50% of minced clams and 50% of carp feed. The African catfish fed with this feed significantly overtook fish from the control group in weight because this feed turned out to be either the most balanced in composition or better absorbed by catfish. In the control group, the 100% mixed feed gave an increase of 83.8% in weight and 20.5% in length; in the experimental group #1, the feed (50% mixed feed : 50% minced mussel) gave an increase of 136% in weight and 31.1% in length; at the experiment #2 (100% minced mussel), the feed gave an increase of 95.5% and 20.1% in length. Originality. For the first time the swan mussel was used as a source of animal protein for African catfish.This experiment was conducted for the first time, and it was also found for the first time that the addition of minced swan mussel to the feed of African catfish contributed to a significant weight gain compared to the conventional feed:52.5% more compared to conventional feed and 40.5% more compared to pure minced swan mussel. Practical value. Aquaculturenow is in search of source of animal proteinin connection with growing global deficit of a high quality fishmeal for fish feed production. Use of bivalve mollusks Anodonta, which are also a pest in pond farms, is promising feed for obtaining physiologically determined weight gains. Key words: aquaculture, Africaт catfish (Clarias gariepinus (Burchell, 1822)), feed, animal protein, plant protein, water quality, swan mussel (Anodonta cygnea (Linne, 1758)), weight gain.

Kajian pemalsuan bekatul dan tepung ikan di Wilayah Jawa Tengah

<p class="MDPI17abstract"><strong>Objective: </strong>The research aimed examine the quality adulteration of bran and fish meal in the Central Java region.</p><p class="MDPI17abstract"><strong>Methods: </strong>The materials used are rice bran and fish meal originating from 17 regions in Central Java which include Rembang, Jepara, Batang, Solo, Boyolali, Pekalongan, Kendal, Temanggung, Magelang, Ungaran, Pati, Purwodadi, Demak, Salatiga, Kudus, Klaten and Semarang. The research method uses descriptive method. Sampling was carried out by purposive random sample to represent the area of the area used as the research site (10 shops in 1 region with different districts and / or villages). Measurement of the parameters of adulteration on bran used Phloroglucinol test, buoyancy test and specific gravity test, while fish meal used urea test.<strong></strong></p><p class="MDPI17abstract"><strong>Results: </strong>The results showed that the bran which was tested for Phloroglucinol and positive buoyancy was faked by adding husks, and was found in the Pati and Demak areas. Density test describes rice bran with non-standard density in Purwodadi, Kendal, Temanggung, Demak and Semarang. Fish meal adulteration occurred in the Boyolali and Pati regions with positive urea content.<strong></strong></p><p><strong>Conclusions: </strong>The conclusion of this research is that good quality of rice bran based on phloroglucinol test, husk floating test and bulk density test were found in Rembang, Jepara, Solo, Boyolali, Magelang, Ungaran, Salatiga and Kudus areas, the quality of fish meal indicated for adulteration based on the urea test was Pekalongan and Purwodadi areas.</p>

The Effects of Varying Heat Treatments on Lipid Composition during Pelagic Fishmeal Production

The study aimed to provide insight into the lipid quality of pelagic fishmeal and fish oil processing of mackerel and herring cut-offs, and the effect of temperature changes in the cooker (85–95 °C) during production. Samples were collected after each processing step at a traditional processing line where water and lipid content, free fatty acids (FFA), phospholipids (PL) and fatty acid composition (FAC) were measured. Results showed that the standard procedures at 90 °C included ineffective draining and concentration steps. Moreover, the solid streams entering the driers variated in chemical composition, suggesting that processing each stream separately could be beneficial for maintaining the lipid quality. The cooking temperature affected the lipid removal from the fishmeal processing, where lowering the temperature to 85 °C resulted in a lower lipid content of the final fishmeal, along with lower FFA and PL values. Hence, the fishmeal and fish oil factories could save energy by lowering the cooking temperature, as well as obtaining more stable and higher value products. Further recommendations include more focus on the initial steps for a better homogenization and breakdown of the raw material, as well as investigation of different drying techniques applied on each processing stream entering the drying steps.

Can Near Infrared Spectroscopy (NIRS) Quantify The Quality of Fishmeal Circulating in Jember, Indonesia?

The objectives of this study were to determine the range of nutrient content of fishmeal circulating in Jember Regency, East Java, and to make a calibration standard for quick calculation using NIRS by R2 and RMSECV. This study used 11 fishmeal samples from around Puger, Jember and around Muncar, Banyuwangi. The physical examination included organoleptic tests (color, odor, and texture), density, and chemical analysis of fishmeal samples. The data obtained were analyzed descriptively. The results indicated that the nutrient content of fishmeal had greatly variation. The CP content presented a quite high ranged between 26.61% to 64.30%. The result of organoleptic test showed the color was yellowish brown, brown, slightly brown to dark brown. The odor was generally standard, which was fishy. Some fishmeal samples were moist in texture, such as fishmeal samples from Jember A (22.03%) and Muncar Banyuwangi B (19.65%). The average of fishmeal density was 0.528 g/ml that ranged between 0.341-0.726 g/ml. The measurement of R2 and RMSECV calibration of fishmeal using NIRS showed good results to predict CF, DM, and EE contents. The usage of NIRS technology was recommended for proximate analysis unless ash content due to the absence of spectrum absorption for minerals.

The Use of Prebiotics and Probiotics in Fish Meal Processing

The use of prebiotics and probiotics in fish meal processing is an alternative method to produce fish meal without boiling, steaming and pressing process. Processing fish meal using prebiotics and probiotics does not produce waste and bad odor that potentially pollutes the environment. This study aims to evaluate physical, chemical and microbiological quality of fish meal processed using two types of prebiotic sources i.e. coconut meal (CM) and palm kernel meal (PKM) and three levels (0; 1 and 2%) of Probio_FM probiotics. The experiment was carried out using a factorial 2 x 3 in complete randomized design with four replications. The variables observed were physical characteristics (aroma, color and texture), microbiological characteristics (number of Lactobacillus spp. and Salmonella colonies), and chemical composition of fish meal (moisture content, crude protein, ether extact and gross energy). The results showed that fish meal processed using prebiotics with or without probiotics had a specific odor of fish meal, light brown color to dark brown, not greasy, not clumping and not indicating physical changes and rancidity after four months of storage. The use of prebiotics combined with Probio_FM produces fish meal free of Salmonella, containing 1010 cfu/g of Lactobacillus spp.; 43, 77 to 45, 81% crude protein; 8, 16 to 11, 35% ether extract; and 4354 to 4529 kcal/kg Gross Energy. It was concluded that the use of coconut meal or palm kernel meal with or without Probio_FM could be applied to produce fish meal as a source of protein as well as source of energy and probiotics, however the combination of prebiotics and probiotics would be better for inhibiting Salmonella growth.

Wheat germ as an alternative ingredient to a fair average quality fishmeal in diets for European seabass

Wheat germ as an alternative ingredient to a fair average quality fishmeal in diets for European seabass

Research on Distinguishing Fish Meal Quality Using Different Characteristic Parameters Based on Electronic Nose Technology.

In this paper, a portable electronic nose, that was independently developed, was employed to detect and classify a fish meal of different qualities. SPME-GC-MS (solid phase microextraction gas chromatography mass spectrometry) analysis of fish meal was presented. Due to the large amount of data of the original features detected by the electronic nose, a reasonable selection of the original features was necessary before processing, so as to reduce the dimension. The integral value, wavelet energy value, maximum gradient value, average differential value, relation steady-state response average value and variance value were selected as six different characteristic parameters, to study fish meal samples with different storage time grades. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA), and five recognition modes, which included the multilayer perceptron neural network classification method, random forest classification method, k nearest neighbor algorithm, support vector machine algorithm, and Bayesian classification method, were employed for the classification. The result showed that the RF classification method had the highest accuracy rate for the classification algorithm. The highest accuracy rate for distinguishing fish meal samples with different qualities was achieved using the integral value, stable value, and average differential value. The lowest accuracy rate for distinguishing fish meal samples with different qualities was achieved using the maximum gradient value. This finding shows that the electronic nose can identify fish meal samples with different storage times.

Alternative protein sources in the nutrition of farm animals

Protein requirement and its demand of farm animals became one of the critical problems in nutrition on a global scale. Protein requirement has been an explicit demand for a long period with soybean meal and animal protein, but recently there are some limitations in relation to their use and the availability of the high quality fishmeal decreases constantly. For this reason there is increased demand for finding new protein sources which could be the alternatives of soybean meal and fishmeal. Alternative protein sources can be divided into seven categories, according to their origin. In different countries, their use depends on the availability in large quantity and at reasonable price.
 There is a long tradition of using legume seeds, as alternatives of soybean. Most of them contain some anti-nutritive compounds, but it can be reduced with systematic selection. Oilseed meals are also generally use in poultry and pig nutrition, but those crude protein content varied, depending on the oil extraction technology. Green fodder and leaf protein was also proposed as alternative protein sources, but their use is limited, in particular because of the market price. The amount of bioethanol and starch industry by-products increases gradually in recent years, therefore those became alternatives of soybean meal, or in much less extend, fishmeal. However, amino acid composition of such by-products are far from optimal for poultry and pig; therefore, in the case of their use amino acid supplementation is necessary. Several novel protein sources are proposed in the last decade, such as algae or insect proteins. Recently, their availability and use is limited, but in the near future those would be alternative protein sources in monogastric animal nutrition.

Fishmeal with different levels of biogenic amines in aquafeed: Comparison of feed protein quality, fish growth performance, and metabolism

The current study investigated the effects of fishmeal quality (low (LB) and high (HB) levels of endogenous biogenic amines) and feed extrusion temperatures (100 and 130 °C) on protein oxidation indicators and amino acids racemization (AAR) in extruded fish feed. Furthermore, the study investigated the accompanying effects on feeding the diets to juvenile rainbow trout (Oncorhynchus mykiss) on fish growth performance, in vivo amino acids (AAs) digestibility, and liver and plasma metabolites following an 8-week feeding trial. A principal component analysis (PCA) showed that better growth performance, secondary oxidation products, and racemized methionine correlated positively with a low content of biogenic amines, whereas the primary oxidation product, protein hydroperoxides, and in vivo AAs digestibility correlated positively with high content of biogenic amines. At an extrusion temperature of 100 °C, the growth performance of the fish decreased when the content of biogenic amines increased. In contrast, at an extrusion temperature of 130 °C, the growth performance was unaffected by the level of biogenic amines. The latter could be a consequence of the higher level of protein oxidation of LB fishmeal compared to HB fishmeal at this temperature. Higher levels of liver pyruvate and plasma lactate together with high level of betaine and AAs in both liver and plasma were associated with the LB fishmeal diets. The lower concentration of AAs especially in liver of fish fed with HB fishmeal demonstrated that these AAs might not be supplied sufficiently for the tricarboxylic acid cycle to generate energy and therefore a decreased growth was found in fish fed this diet. Furthermore, the results indicated that biogenic amines and feed attractants such as betaine are more decisive for evaluating the quality of fishmeal than protein quality parameters.

The effects of increasing dietary levels of soy protein concentrate (SPC) on the immune responses and disease resistance (furunculosis) of vaccinated and non-vaccinated Atlantic salmon (Salmo salar L.) parr

Juvenile salmon, with an initial weight of 9 g, were fed three experimental diets, formulated to replace 35 (SPC35), 58 (SPC58) and 80 (SPC80) of high quality fishmeal (FM) with soy protein concentrate (SPC) in quadruplicate tanks. Higher dietary SPC inclusion was combined with increased supplementation of methionine, lysine, threonine and phosphorus. The experiment was carried out for 177 days. On day 92 salmon in each tank were bulk weighed. Post weighing eighty salmon from each tank were redistributed in two sets of 12 tanks. Salmon from the first set of tanks were vaccinated, while the second group was injected with phosphate buffer saline (PBS). Salmon were sampled on day 92 (pre-vaccination), day 94 (2 days post vaccination [dpv]/PBS injection [dpPBSinj]) and day 154 (62 dpv/dpPBSinj) of the trial for the assessment of their immune responses, prior to the performance of salmon bulk weights for each tank. On day 154, fish from each tank were again bulk weighed and then seventeen salmon per tank were redistributed in two sets of twelve tanks and intra-peritoneally infected with Aeromonas salmonicida. At Day 154, SPC80 demonstrated lower performance (weight gain, specific growth rate and thermal growth coefficient and feed conversion ratio) compared to SPC35 salmon. Reduced classical and total complement activities for salmon fed diets with over 58% of protein from SPC, were demonstrated prior to vaccination. Reduced alternative complement activity was detected for both SPC58 and SPC80 salmon at 2 dpv and for the SPC80 group at 62 dpv. Total and classical complement activities demonstrated no differences among the dietary groups after vaccination. Numerical increases in classical complement activity were apparent upon increased dietary SPC levels. Increased phagocytic activity (% phagocytosis and phagocytic index) was exhibited for the SPC58 group compared to SPC35 salmon at 62 dpPBSinj. No differences in serum lysozyme activity, total IgM, specific antibodies, protein, glucose and HKM respiratory burst were detected among the dietary groups at any timepoint or state. Mortalities as a result of the experimental infection only occurred in PBS-injected fish. No differences in mortality levels were demonstrated among the dietary groups. SPC58 diet supported both good growth and health in juvenile Atlantic salmon while SPC80 diet did not compromise salmon’ immunity or resistance to intraperitoneally inflicted furunculosis.

Growth performance and quality traits of European sea bass (D. labrax) fed diets including increasing levels of freeze-dried Isochrysis sp. (T-ISO) biomass as a source of protein and n-3 long chain PUFA in partial substitution of fish derivatives

Abstract The aim of this study was to evaluate nutrient digestibility, growth performance, biometry, dressing out parameters, fillet muscle proximate and fatty acid composition of European sea bass ( Dicentrarchus labrax L.) of nearly marketable size, fed increasing levels of a freeze-dried biomass of Isochrysis sp. (clone T-ISO) as a partial substitute for protein and lipid from fish derivatives, in diets where the level of n-3 long chain (LC) PUFA were reduced through a partial replacement of fish oil for crude palm oil. Since diets including the test ingredients could possibly result in changes of certain quality attributes, fish were also subjected to overall sensory evaluation by a trained panel of assessors according to a triangle test. Three diets were formulated to be grossly iso -nitrogenous (N, 7.5% dry matter). A preparation in which fish meal/trimmings and fish oil were the major protein and lipid sources was used as a positive control diet. Two test complete diets were obtained from the control preparation so that approximately 10 and 20% crude protein from a high quality fish meal and 18 and 36% lipids from fish oil were supplied by the dried microalgae biomass. To stress the role of Isochrysis sp. as a source of n-3(LC)PUFA, the diets including increasing levels of the microalgae biomass were made grossly iso -caloric–lipidic by replacing a part of fish oil with palm oil which is known to be virtually free from n-3 PUFA. Each diet was fed to apparent satiety to quadruplicate groups of sea bass (142 g) over 121 days. The results have shown that replacing up to 20% crude protein from fish meal with a dried Isochrysis biomass and up to 36% fish lipid for those supplied by the microalgae in a diet with reduced level of fish oil, did not adversely affect feed intake or growth performance relative to controls even if the highest substitution rate resulted in a decline (P

Fishmeal quality and ethoxyquin effects on the weaning performance of ballan wrasse (Labrus bergylta) larvae

Fishmeal diets are shown to be unfavourable for successful weaning of ballan wrasse (Labrus bergylta) larvae. Variable fishmeal quality, and/or a possible negative effect of ethoxyquin (EQ) and/or palatability could be the reason for the reduced growth and increased mortality observed. This study weaned wrasse larvae on either a control diet of freeze–dried shrimp and cod fillet, or fishmeal-based diets with 0, 11 or 44 ppm EQ, for 1 month. Lower final body weight and higher mortality were related to increased inclusion of EQ. Furthermore, fishmeal diets had increased lipid oxidation values with decreased EQ content, whereas the control diet had the lowest lipid oxidation levels. A combined negative effect of oxidation and EQ supplementation could have lowered the palatability of the feeds and be the reason for the unsuccessful larval weaning. Use of EQ is inevitable in large-scale production of feed ingredients; however, the use of high-quality ingredients with low EQ inclusion, or its replacement with other antioxidants, may be necessary for successful intensive culture of some marine fishes.

Comparative environmental performance of artisanal and commercial feed use in Peruvian freshwater aquaculture

We used Life Cycle Assessment (LCA) to evaluate some of the environmental implications of using commercial versus artisanal feeds in Peruvian freshwater aquaculture of trout ( Oncorhynchus mykiss ), tilapia ( Oreochromis spp.) and black pacu ( Colossoma macropomum ). Several scenarios believed to be representative of current Peruvian aquaculture practices were modelled, namely: production of trout in Andean lake cages; and culture of black pacu and tilapia in Amazonian and coastal lowland ponds, respectively. In general, Peruvian aquaculture is characterised by low technological intensity practices. Use of commercial aquafeeds is widespread, but artisanal feeds are frequently used in certain small-scale farms. We found that trout feeds feature higher environmental burdens than do black pacu and tilapia feeds. A similar trend is observed for production of these species. Across species, the substitution of artisanal with commercial feeds, despite improving feed conversion ratios in all cases, does not always reduce overall environmental impacts. This is due to the additional energy use and transportation requirements associated with commercial feed inputs. The substitution of artisanal feeds with commercial ones generally increases environmental impacts of the fish farming systems for the specific feeds considered, despite enhanced FCRs and economies of scale. This is due to the higher environmental impacts associated to certain feed inputs used in commercial feeds, in particular highly refined feed inputs. Consequently, in light of the importance of feeds to overall life cycle impacts of aquaculture production, the Peruvian aquafeed industry should preferentially source less refined and, in general, less environmentally burdened feed inputs (e.g. Bolivian soybean products over Brazilian, high quality over lower quality fishmeal, avoiding protein concentrates, etc.), to the extent that fish farming performance (i.e. feed conversion efficiency and cost structure) is not strongly affected. Among species, black pacu aquaculture shows the best environmental performance. • Substitution of artisanal feeds with commercial ones increases environmental impacts. • Higher impacts are due to highly refined, energy-intensive feed inputs. • Sourcing of agricultural feed inputs affects environmental performance of feeds. • Prime instead of residual fishmeal should be used for artisanal feeds. • Black pacu aquaculture has better environmental performance than other species.

Marine and freshwater crab meals in diets for red porgy ( Pagrus pagrus ): Digestibility, ammonia-N excretion, phosphorous and calcium retention

Abstract Two trials were conducted to evaluate the nutrient digestibility of river crab (RC) ( Procambarus clarkii ) and marine crab (MC) ( Chaceon affinis ) meals in diets for red porgy ( Pagrus pagrus ) and the effect on ammonia-N excretion and P and Ca retentions. In trial I, the apparent digestibility coefficient (ADC) of nutrients and energy contents in RC and MC meals were determined. Results showed that, the ADC values for protein, lipids, ash, dry matter and gross energy were significantly higher for MC than for RC meal. Both crab meals were efficiently digested despite their high chitin and ash contents. In trial II, red porgy were fed over 6 months with five diets: a control diet (CD) based on high quality fish meal (FM), and four diets where FM protein was replaced at a rate of 10% or 20% by protein derived from either RC or MC meal (RC10, RC20, MC10 and MC20). Replacement of the FM protein by RC or MC proteins had no effect both on protein utilisation and ammonia-N excretion rates, which ranged from 105 to 119 mg N–NH 4 + kg − 1 day − 1 for all diets. A linear increase was observed in the dietary Ca/P ratio by the increase of the dietary RC and MC meal inclusions, resulting in a reduction in the whole fish body content of P, Ca and ash with interesting similar whole body Ca/P ratio (1.59–1.63) for all treatments. Accordingly, Ca, P and ash retention rates were significantly reduced by increasing the dietary proportion of both crab meals. Moreover, a negative relationship between fish growth and final whole body Ca, P and ash contents was obtained. However, no significant differences were observed in total P excretion value (kg P t − 1 ).